Blender 2.77 Mac Installation-Python 3.5 files could not be opened
I learned that my problem was due to using an outdated version of The Unarchiver (version 1.0.1) to unzip the Blender 2.77a zip file. Upgrading OSX over the years did not upgrade this utility. Installing the most recent version of The Unarchiver from the App Store allowed me to unzip the Blender file normally with no error messages.